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The ActiveXObject object in JavaScript is a reference that enables and returns an Automation object.
Usage: newObj = new ActiveXObject( servername.typename[, location])FileSystemObject object To implement file manipulation functions in javascript, the main thing is to rely on the FileSystemobject object.
Second, FileSystemObject programming Using the FileSystemObject object for programming is very simple, generally through the following steps: Create a FileSystemObject object, apply related methods, access object related properties.
(1) Create a FileSystemObject object The code for creating a FileSystemObject object is as long as 1 line: var fso = new ActiveXObject("Scripting.FileSystemObject"); After the above code is executed, fso becomes a FileSystemObject object instance.Fourth, the operation folder (Folders) operations related to the folder include creating, moving, deleting and obtaining related properties.
Folder object operation routine: The following routine will practice to get the parent folder name, create a folder, delete the folder, determine whether it is the root directory, etc.
The code is as follows:
var fso, fldr, s = ""; // Create FileSystemObject object instance fso = new ActiveXObject("Scripting.FileSystemObject"); // Get the Drive object fldr = fso.GetFolder("c:"); // Display the parent directory name alert("Parent folder name is: " + fldr + "n"); // Display the drive name alert("Contained on drive " + fldr.Drive + "n"); // Determine if the root directory is if (fldr.IsRootFolder) alert("This is the root folder. "); else alert("This folder isn't a root folder."); alert("nn"); // Create a new folder fso.CreateFolder ("C:Bogus"); alert("Created folder C: Bogus" + "n"); // Display the folder base name, without the path name alert("Basename = " + fso.GetBaseName("c:bogus") + "n"); // Delete the created folder fso.DeleteFolder ("C:Bogus"); alert("Deleted folder C:Bogus" + "n");
Fifth. Operation files (Files)
The operation of the file is more than the above The Drive and Folder operations are more complicated and basically divided into the following two categories: creation, copying, moving, deleting, and creating, adding, deleting, and reading of file contents. . The details are described below.
(1) create a file There are three ways to create an empty text file, sometimes called a text stream (text stream).
The first is to use the CreateTextFile method.
code show as below:
Var fso, f1; fso = new ActiveXObject("Scripting.FileSystemObject"); f1 = fso.CreateTextFile("c:testfile.txt", true); The second is to use the OpenTextFile method and add the ForWriting property, ForWriting The value is 2.
The code is as follows: The code is as follows: var fso, ts; var ForWriting= 2; fso = new ActiveXObject("Scripting.FileSystemObject"); ts = fso.OpenTextFile("c:test.txt", ForWriting, true); To use the OpenAsTextStream method, also set the ForWriting property. The code is as follows: var fso, f1, ts; var ForWriting = 2; fso = new ActiveXObject("Scripting.FileSystemObject"); fso.CreateTextFile ("c:test1.txt"); f1 = fso.GetFile("c:test1 .txt"); ts = f1.OpenAsTextStream(ForWriting, true);
(2) add data to the file
After the file is created, generally follow the steps of "Open File -> Fill Data -> Close File" to add data to the file. To open a file, use the OpenTextFile method of the FileSystemObject object, or use the OpenAsTextStream method of the File object. Fill in the data to use the Write, WriteLine or WriteBlankLines methods of the TextStream object. In the same function of writing data, the difference between the three is that the Write method does not add a new line break at the end of the write data, the WriteLine method adds a new line break at the end, and WriteBlankLines adds one or more spaces. Row. Close the file to use the Close method of the TextStream object.
(3) create files and add data routines
The following code combines the steps of creating a file, adding data, and closing a file: The code is as follows:
Var fso, tf; fso = new ActiveXObject("Scripting.FileSystemObject"); // Create a new file tf = fso.CreateTextFile("c:testfile.txt", true); // Fill in the data and add a newline tf. WriteLine("Testing 1, 2, 3.") ; // Add 3 blank lines tf.WriteBlankLines(3) ; // Fill in a line without the line break tf.Write ("This is a test."); / / Close the file tf.Close();
(4) Reading the contents of the file
To read data from a text file, use the Read, ReadLine, or ReadAll methods of the TextStream object. The Read method is used to read a specified number of characters in a file; the ReadLine method reads an entire line, but does not include a newline character; the ReadAll method reads the entire contents of a text file. The read content is stored in a string variable for display and analysis. When using the Read or ReadLine method to read the contents of a file, if you want to skip some parts, use the Skip or SkipLine method. The following code demonstrates opening a file, filling in the data, and then reading the data: The code is as follows:
Var fso, f1, ts, s; var ForReading = 1; fso = new ActiveXObject("Scripting.FileSystemObject"); // Create file f1 = fso.CreateTextFile("c:testfile.txt", true); // Fill in One line of data f1.WriteLine("Hello World"); f1.WriteBlankLines(1); // Close the file f1.Close(); // Open the file ts = fso.OpenTextFile("c:testfile.txt", ForReading); // Read a line of content from the file to the string s = ts.ReadLine(); // Display the string information alert("File contents = '" + s + "'"); // Close the file ts.Close();
(5) Moving, copying and deleting files
For the above three file operations, javascript has two corresponding methods: File.Move or FileSystemObject.MoveFile for moving files; File.Copy or FileSystemObject.CopyFile for copying files; File.Delete or FileSystemObject.DeleteFile for deleting file. The following code demonstrates creating a text file in the root directory of drive C, filling in some content, then moving the file to the tmp directory, then creating a file copy under the directory temp, and finally deleting the files in both directories: The code is as follows :
Var fso, f1, f2, s; fso = new ActiveXObject("Scripting.FileSystemObject"); f1 = fso.CreateTextFile("c:testfile.txt", true); // Write a line f1.Write("This is a Test."); // Close the file f1.Close(); // Get the C: root file handle f2 = fso.GetFile("c:testfile.txt"); // Move the file to the tmp directory f2 .Move ("c:tmptestfile.txt"); // Copy the file to the temp directory f2.Copy ("c:temptestfile.txt"); // Get the file handle f2 = fso.GetFile("c:tmptestfile.txt "); f3 = fso.GetFile("c:temptestfile.txt"); // Delete file f2.Delete(); f3.Delete();
Sixth. Conclusion
Through the above introduction and examples of the various objects, properties and methods of FileSystemObject, I believe that you have a clear understanding of how to use the javascript language to operate drives, files and folders in the page. However, the above mentioned routines are very simple. To master the javascript file operation technology comprehensively and flexibly, a lot of practical exercises are needed. And there is another reminder that because of the advanced operations involved in file reading and writing in the browser, for the default browser security level, there will be a message prompt before the code runs. Please do this in the actual environment. Prompt visitors to pay attention.
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